Symbiosis
by Queen of the Castle
Summary: The Doctor loses something, but not everything.  Ten/TARDIS, Ten/Rose


The impacts of his footsteps were heavy on the grating as the Doctor trudged over the threshold into the TARDIS. He hesitated to let the TARDIS door fall shut for a moment purely out of habit firmly ingrained over the past two years, though he hadn't really managed to _forget _for a single second that there would be no one following him into his ship today. Where just a few hours ago he'd been seemingly surrounded by talkative Tylers, now...

Now it was just him. Again.

The TARDIS apparently found their absence notable – or perhaps she simply detected his obviously distressed reaction to it – for she made what sounded on initial reflection like an inquisitive noise. He quickly realised, though, as his mind stopped focusing exclusively elsewhere (universes away) and took in the full context of the sound, that it wasn't just a matter of simple curiosity. She was _concerned_. It wasn't just about where her pink and yellow passenger had disappeared off to and what kind of trouble she might be getting into on her own (don't wander off – yet another of his rules that the two of them should never have so thoroughly smashed). She also seemed worried about why her Time Lord was sending out a signal proclaiming that he was somehow in need of repair.

The Doctor laughed bitterly. She might be alive, but that didn't mean that the TARDIS' thought processes weren't often closer to that of machinery than of people. In this case, though, her classifying him as 'broken' wasn't far off at all.

The Doctor leaned tiredly against the wall and stared at the console. _She _should have been standing right there beside it, tempting him with a smile and that adorable way she sometimes tilted her head, urging him to take them to some wild 78th century party where the Doctor knew the men would throw themselves at her in a way that would drive him half mad, but where he'd undoubtedly end up taking her anyway because he couldn't ever seem to say no to her for long. Not even when it mattered most.

He should have kept telling her no when she'd tried to promise him forever. He'd managed initially to explain to her why it was impossible, and why he had to hold her at arm's length. It had hurt both of them to hear the words said aloud so definitively, but he had done it. He should have been able to just keep reminding her, and reminding himself at the same time, and that should have been enough. But somewhere along the line it seemed that she'd said she would stay with him often enough that he'd started to let himself believe in it and in them (the same way it hadn't taken him long at all before he'd started believing in _her _above everything).

He should have known better. He _had_, once upon a time. It was why he had these rules in the first place. He'd already lost more than enough in his long life to be well aware how his story was destined to end. Building his hopes up like that only meant there was so much further to fall when she eventually did leave and took everything that mattered with her.

"She's gone," he finally said aloud, as if the silence hadn't already been enough to make Rose Tyler's absence feel painfully real.

The TARDIS let out a mournful note at the news, but it was clear that she didn't feel the pain anywhere near as acutely as he did. _She'd _never forgotten the inevitability of it. With all of time and space running through her heart, there was no way she ever could. In fact, somewhere deep inside, she'd probably always known exactly when it was going to happen right down to the second.

The Doctor felt a moment of rising anger as he considered that maybe it was as much the TARDIS' fault as his that Rose was gone. The TARDIS could easily have refused to let them land right there and then, or at least let him know what was bound to happen there. Even without ever using what lesser beings would consider actual language, she could be more than talkative enough when she wanted. So how could she have failed to speak up when it really mattered? Hadn't she wanted to keep Rose with them? All three of them could have driven off and never set foot on 21st century Earth ever again. They could have run and run and run and never looked back, and they could have been happy. He could have found another place to pick up milk (though he really did prefer it from the cows that were farmed around this timeframe), and not having to visit Jackie would have been a blessing (he pointedly shoved away the pang at the realisation that she was now permanently out of his reach as well), and Earth could just self-destruct or be overwhelmed by aliens in his absence if that was what it took to keep _her_safe (though that thought sounded completely hollow; even though it would have probably served Torchwood right for thinking they were capable of controlling even that one stupid little planet of theirs, he couldn't actually fool himself into believing that either he or Rose would have allowed their idiocy to cause harm to that planet, no matter the personal risk to either of them).

His inner rage was short-lived, as he realised that he couldn't quite blame the TARDIS for keeping the information to herself, if she'd known it. He'd probably just have ignored any warnings she might have given anyway. He hadn't wanted to know. Even the vaguest sense that something was coming had been bad enough. He hadn't been ready to confront the possibility of losing anyone who meant so much to him again, so close on the heels of the Time War.

But whether he wanted to face up to it or not, with each of those costly failures of his piling up, once again the TARDIS now seemed to be all that remained.

He nodded slightly at the thought, reminding himself that he wasn't actually _alone_. He never had been, even through the worst of it.

He stroked the nearest strut and the coral vibrated beneath his hand.

"How long are _you_going to stay with me?" he asked her sadly, feeling the empty echo of déjà vu keenly.

The TARDIS pulsed in answer, her meaning crystal clear. The Doctor wondered whether it was any less risky to let himself believe that promise a second time around, given that this time it was coming from his ship. Granted, the TARDIS had stayed with him much longer than anyone else ever had, but he found it difficult to shake the suspicion that his penchant for losing everything would ultimately end up including her one day.

Nonetheless, he readily returned her vow, responding with that loaded word: "Forever." He had to put away the reminder of how dangerous a thing that was to promise, for he needed to believe in it now more than ever. He couldn't lose _her _– his ship, his life – on top of everything else.

He remembered hovering just miles away from the rending death that awaited them all inside a gaping black hole. Even with Rose there to valiantly attempt to ease the pain, the thought that he might have lost his wonderful TARDIS for good would have been completely crippling, if he'd allowed himself to truly believe for more than that very first dark moment that it could be permanent.

He knew that he'd felt more for Rose than he had any of the other people he'd travelled with (which was saying something, because he honestly cared for them all, even the ones that he'd rather choke on his own tongue than actually admit that to), but the TARDIS was different. More. _Everything_.

As always with her, he didn't need to put a voice to it. She seemed able to read him better without words getting in the way of his true meaning. She felt his unspoken words and a song filled the air in response. As she did with almost everything (what would he do without her?), she translated for him. He belonged to her, the music chimed, and she wouldn't leave him. He was everything to her as well. So she would help him through this loss, just as she always had, and did, and would.

The TARDIS unexpectedly sprang into motion of her own accord, then. Her supposed pilot could do nothing more than grab at the wall to steady himself as the ship shuddered through time and space without his input. He just barely avoided ending up face down on the sharp metal floor when she halted. The Doctor frowned, finding his feet again, and then went to survey the monitors.

A supernova, he recognised immediately. The TARDIS had parked them in orbit around a supernova in the year fifty-three slash orange slash delta.

Rose would have liked to see this, he thought, and then wished that hadn't occurred to him.

"It's beautiful," the Doctor admitted, caressing the control panel, "and I get why you might think it would help – the universe going on and being brilliant no matter what else happens, just like it always will even after everything else is gone – but sorry to say I think you're going to have to give me a bit of time before I can properly appreciate it. I'm not like the universe. I'm not ready to just keep on turning. Not yet."

The TARDIS sounded impatient, the same way he knew he often sounded when his companions just somehow failed to grasp the obvious (or what was completely obvious to _him_, at any rate).

The TARDIS whispered into his mind, an image and a feeling. "Rose," she insisted, as if just the word should be enough for him to understand.

And it suddenly was. She _helped _him understand, just like always.

"Oh," the Doctor breathed. Of course. His head was so thick and full of feelings and self-pity and all sorts of bits and bobs and rubbish that the TARDIS was one hundred percent dead-on right; he'd missed something that was right in front of him, as though he was some kind of... of... _human_.

Perhaps broken was the right word after all. And even with enough power at his disposal to break temporarily through time and space and even the Void itself (to a point), this wasn't an instant fix by any stretch of the imagination (even _his_ imagination). But it was a start. His beautiful ship had given him a way to start the process of 'repairing' himself, much the same way he often helped her fix herself up when only a pair of corporeal hands could do the job.

Underneath the surface calm, he was overwhelmed with love for her. His TARDIS cared enough about her Time Lord to help him do this, without him even having to ask. That meant just as much to him as the actual ability to see Rose one last time, even if it was just to say goodbye. Maybe it was even worth _more_, come to that.

As he got to work putting the TARDIS' stroke of genius to good use, he said, "Thank you." The ship let out a low whoosh, and he knew that she sensed the three words he was _really _saying underneath the cover of those far simpler ones.

With her, he knew it would never really need to be said.

She'd always understood him best.


End file.
